An example of a change-point detection apparatus according to the prior art is described by V. Guralnik and J. Stivastava (see V. Guralnik and J. Stivastava, “Event Detection from Time Series Data”, Proceedings of the Fifth ACM SIGKDD International Conference on Knowledge Discovery and Data Mining, pp. 33–42, ACM Press, 1999). The scheme according to V. Guralnik and J. Stivastava calculates the sum total of fitting errors in a case where curve fitting has been performed on the assumption that there are no change points and the sum total of fitting errors in a case where curve fitting has been performed separately before and after change-point candidates, and deciding that a change point has occurred if the difference between the sum totals exceeds a certain value.